Re: "Transient Eyelid Edema Following COVID-19 Vaccination".

To the Editor:

We would like to share ideas on “Transient Eyelid Edema Following COVID-19 Vaccination.” [1] Post–COVID-19 vaccination, ocular problem is an interesting clinical issue. Austria et al[1] discussed on possible immunopathological mechanism causing eyelid edema. However, there is no evidence of any abnormal immune laboratory parameters in this patient. In addition to immunity problem, the abnormality might also be explained by other pathobiological process. After COVID-19 vaccination, there might be a hyperviscosity problem.[2] Ocular edema is a rare but possible clinical presentation of a patient with hyperviscosity, such as a case with underlying myeloma.[3] The vaccine-induced hyperviscosity is due to rapid surge on immunoglobulin after vaccine administration, and the viscosity will decrease when time passes.[2] This might be an explanation for occurrence of transient ocular problem.